The spleen is an extremely vascular organ and consequently splenic rupture can cause large intraperitoneal haemorrhage, rapidly leading to fatal haemorrhagic shock.
The majority of cases of splenic injury are secondary to abdominal trauma, in particular blunt trauma. Common situations in which the spleen is injured include seat-belt injuries in road traffic collisions and falls onto the left side (such as patients slipping on ice or elderly patient falling in the bathroom).
A minority of cases are iatrogenic, or secondary due to underlying splenomegaly from haematological malignancy or infective causes (such as Epstein-Barr virus). In these cases, as the spleen grows in size, the capsule stretches and thins, becoming more fragile. This puts it at an increased risk of rupture.
Diagnosis is most commonly made from the investigations of abdominal pain following a history of trauma. Patients may complain of abdominal pain or clinical features of hypovolaemic shock, yet only imaging will confirm the diagnosis.
On examination, patients may have left upper quadrant tenderness and / or peritonism (which will become more generalised as the blood loss increases). Free blood can irritate the diaphragm and cause a radiating left shoulder pain (known as Kehr sign).
Patients who are haemodynamically unstable with peritonism following trauma have abdominal bleeding until proven otherwise and require immediate laparotomy.
Those who are not haemodynamically unstable with suspected abdominal injury will need an urgent CT chest-abdomen-pelvis with IV contrast.
CT scans allow for the identification and assessment of splenic injury, alongside any other abdominal viscera involvement. Specifically, it also allows for the grading of the splenic injury to guide further management.
FAST scans in the emergency department setting can reveal free peritoneal fluid or fluid in the pericardium. However, whilst helpful, they should not delay CT imaging and / or surgical intervention.
Organ Injury Scale
The American Association for the Surgery of Trauma (AAST) splenic injury scale is the most commonly used system for grading splenic trauma. It is used to help guide which patients are likely to benefit from conservative management and which need surgery.
Grade of Injury
|– Capsular tear <1cm parenchymal depth
– Subcapsular haematoma <10% surface area
|– Capsular tear 1-3cm parenchymal depth
– Subcapsular 10-50% surface area, or intraparenchymal <5cm
|– Capsular tear >3cm parenchymal depth, or any tear involving trabecular vessels
– Subcapsular >50% surface area, or intraparenchymal >5cm, or any expanding or ruptured haematoma.
|– Laceration involving segmental or hilar vessels, devascularising >25% of the spleen|
|– Completely shattered spleen or hilar vascular injury, devascularising the entire spleen|
All patients with suspect splenic injury should be assessed, resuscitated, and treated according to ATLS principles.
Patients who are haemodynamically unstable* or with a grade 5 injury (a shattered spleen or major hilar vascular injury) need urgent laparotomy.
*If there is evidence of active extravasation of the contrast during the arterial phase of the CT scan, the patient should undergo embolisation (if locally available) or laparotomy with splenectomy.
Haemodynamically stable patients with grade 1 – 3 injuries without active extravasation can be treated conservatively.
They should be resuscitated as appropriate, admitted to a high dependency area for observation, and have serial abdominal examinations for any evidence of deterioration.
With any evidence of increasing tenderness or peritonitis, there should be a low threshold for re-imaging and / or laparotomy (as associated injuries such as small bowel injuries are easily missed on initial CT imaging).
All patients who are treated conservatively should receive prophylactic vaccinations (against Strep Pneumoniae, Haemophilus Influenzae B (HIB) and Meningococcus) at discharge.
Complications of Treatment
The main complications of conservative treatment or embolization are:
- Ongoing bleeding
- Splenic necrosis
- Splenic abscess formation
- Splenic cyst formation
Overwhelming Post-Splenectomy Infection (OPSI)
The spleen is an immunologically active organ, with an active role in destroying encapsulated organisms, such as Pneumococcus, Meningococcus, and H. Influenzae. Asplenic patients are therefore unable to mount a normal immunological response against these organisms and infection can lead to overwhelming sepsis.
Consequently, any asplenic patient, including those post-splenectomy, should receive vaccinations against these three organisms. In addition, prophylactic Penicillin V should be considered (this may not be required lifelong in low-risk patients).
- Patients who are haemodynamically unstable with peritonism have abdominal bleeding until proven otherwise and require immediate laparotomy
- Patients who are not haemodynamically unstable with suspected abdominal or chest injuries need an urgent CT chest / abdomen / pelvis with IV contrast.
- All patients should be assessed, resuscitated and treated according to ATLS principles
- Patients who are haemodynamically unstable or with a grade 5 injury (a shattered spleen or major hilar vascular injury) need urgent laparotomy.